Apparatus for treatment of strands



March 17, 1953 w. T. R. KINRAIDE APPARATUS FOR TREATMENT OF STRANDSFiled June 30, 1949 ATTORNEY Patented Mar. 17, 1953 UNITED STATES ATENTOFFICE APPARATUS FOR TREATMENT OF STRANDS ware Application June 30,1949, Serial No. 102,216

Claims.

This invention relates to the treatment of traveling strands such asfilms or filamentary material. More particularly, it relates to achamber provided with a specially constructed orifice and to the use ofthis chamber in the treatment of continuous strands traveling throughthe chamber.

The utilization of fluids such as steam in the manufacture offilamentary materials has been handicapped by the diificulties involvedin handling the fluid which is generally used at elevated temperaturesand under pressure. For example, steam is induced into a chamber throughwhich a yarn is passing and it escapes out into the atmosphere throughthe inlet and outlet holes through which the yarn passes. Specialmethods hitherto known for preventing the escape or for handling theescaping fluid have been for the most part unsatisfactory and costly.Further, thees precautionary measures have not satisfactorily broughtabout an immediate separation of the escaping fluid from the travelingstrand. Adherent disadvantages are yarn damage, difflcult operation,undesirable humidity build-up and atmospheric contamination. Stillfurther, such currents prevent a rapid cooling or hardening of thematerials after leaving the treating chamber.

Accordingly, it is an object of this invention to provide a simpleapparatus for the treatment of a continuous strand such as a film, ayarn, a continuous filament or the like which avoids the above mentioneddifficulties. It is a further object of this invention to provide asimple means for separating the treating fluid from the strandimmediately and completely at the desired points. A further object ofthis invention is the provision of a simple chamber through which manystrands may be passed simultaneously and uniformly treated. Furtherobjects and advantages of this invention will be apparent hereinafter.

The above-mentioned objectives are accomplished by the herein describedapparatus for treating a continuous strand with a fluid which apparatuscomprises a substantially closed chamber for the treating fluid andinlet and outlet orifices through which the strands pass and out ofwhich the fluid emerges, the said orifices being formed by two roundedges preferably having different radii. The distance of one round edgefrom the other edge is for most purposes not more than 0.05 inch. Thefluid as it leaves the chamber follows the curved surface of the roundededge having the larger radius whereas the strand continues in a directpath generally perpendicular to the orifice. An immediate and completeseparation of the strand and the fluid is made through the use of thisnovel orifice. The treating fluid is made to turn and flow in a rapidlydiverging path away from the yarn.

The invention will be more clearly understood by reference to thediscussion below and to the figures which are given for illustrativepurposes and of which:

Figure 1 is a longitudinal cross section showing the relationship of thestrand, the path of the strand and that of the fluid;

Figure 2 is an end view showing a plurality of the strands;

Figure 3, taken on line 3-3 of Figure 4 illustrates one embodiment ofthis invention in which cylinders or rods of diiferent diameters areused in the formation of the orifice;

Figure 4 shows the grooved cylinder of Figure 3 from an end view;

Figure 5 illustrates another embodiment of this invention and Figure 6illustrates still another embodiment of the invention.

Referring to the figures, the chamber I is formed by a top 2, top endwalls 3, a bottom 4 and bottom end walls 5 and side walls (not shown).In the top 2 is any appropriate inlet valve i. In the bottom 4 there isa drain or trap It for removal of condensate from the cell body. Top endwalls 3 and the bottom end walls 5 lie very closely together formingslot II and allowing the chamber to be substantially closed. The slot IIso formed may be made by cutting out the desired section of the endplate or the top and bottom sections may be bolted together at E. Theedge or lip 8 of the top walls 3 and the edge or lip 9 of the bottomwalls 5 are rounded in such a manner that the radius of one of therounded edges is larger than the radius of the other rounded edge. Asshown in Figure 1, the lip 8 has a radius, designated by r, smaller thanthat of lip i? which radius is designated by R. The distance separatingthese two rounded edges is designated by the letter T, as shown inFigure 1. The continuous strand Ill passes through the orifice or slotII formed by the rounded edges 8 and 9. The fluid inserted underpressure through the valve i strikes the strand Ill as it passes throughthe chamber I. The fluid flows out through the orifice I I and followsthe surface of the rounded edge having the larger diameter as shown bythe dotted lines I2. The fluid and the strand are immediately separated.An appropriate collecting means, such as a funnel 13 or any othersimilar device is used to carry away the fluid for recovery orrecycling. As shown in Figure 2, which is an end view, a plurality ofyarns may be passed through the chamber to receive uniform treatment.Each strand is drawn through the chamber at a uniform rate and is woundup by any appropriate winding mechanism (not shown). The separation ofthe treating vapors from the strands is simple, automatic and completeand the apparatus is inexpensive to build and basically simple tooperate.

As shown in Figure 5, the bottom wall need not be of uniform diameterfor all that is necessary is a curved surface extending far enough tocarry the fluid sufficiently far from the yarn to effect the separation.In such a device as that shown in Figure 5 the ratio of the radii maybe, for example,

and the distance T may be 0.015 inch. A chamber equipped with suchorifices may be operated efficiently at pressures within the chamber offrom 5 lbs. to 50 lbs. gauge with atmospheric pressures prevailingoutside of the chamber.

In another embodiment, shown in Figure 3, two rods or cylinders, l4 andii of different diameters are mounted on suitable plates. an apparatusthe ratio of the radii may be, for example,

and the distance T may be 0.010 inch. As shown in Figure 4, one of thecylinders preferably the one having the smaller radius may be grooved.This grooved cylinder serves the dual purpose of the upper lip and of acomb guide. The grooves l9 in the upper cylinder may have a radius of0.010 inch. A notched efiect added to the lip facing provides sufiicientclearance to permit the yarn to be crossed under running ends. Thisallows for ease of string-up at the start of operation and if breakageoccurs. Grooves are not essential, for with smooth lips an externalguide may be located close to the lips. However, it is preferred forsimplicity and for economy in space to use grooved lips. Only one isneeded and it has been found that best results are obtained by runningthe yarn in grooves in the upper lip. Effective control and preventionof sidewise fluttering is obtained using a grooved upper lip.

In still another embodiment shown in Figure 6, for example 1' is inchand R is d; to inch; the lower wall 5 is provided with an escape slot I7and a lateral passage 13. This slot is set so that 80% to 90% of thefluid, such as steam is carried off through the lateral passage forrecycling or recovery. The remaining 10% to goes around the outside toan exhaust duct such as duct I3. This device has the advantage ofreducing entrainment of air and disturbance of the yarn or article beingprocessed. Further, the upper lip is so designed to facilitate furtherthe separation of the fluid from the yarn.

The apparatus of this invention may be used for various purposes, as,for example, in subjecting films, yarns, and continuous moncfilaments ormultifllaments to steam or other vapors under pressure aboveatmospheric. The apparatus may be employed with particular advantage inthe treatment of continuous artificial filamentary structures, such asthose of cellulose In such 4 esters and ethers, regenerated cellulose,polyamide and polyester materials, and of other synthetic materials suchas polyvinylidene chloride, polyvinyl chloride, copolymers of vinylchloride and vinyl acetate, after-chlorinated polyvinyl chloride,polyacrylonitriles, as well as those of proteins such as casein or soyabean protein.

In a specific example, a plurality of polyacrylonitrile yarns werepassed through the chamber. Each of the yarns forming the warp left thechamber and were then passed around a series of positively driven rolls,the peripheral speed of which was 8 times that of the feed rolls whichmetered the yarns off a pirn or package. The steam in the treatingchamber was kept at 20 lbs. gauge pressure. The polyacrylonitrile yarnin passing through this chamber under these conditions was drawn 8 timesits original length. The treated yarn had a uniform denier along itslength and possessed a uniform tenacity of 4.9 grams per denier and auniform elongation of 19%. The undrawn, untreated yarn had a lowtenacity of about 0.5 gram to 1.0 gram per denier and a low elongationof about 5 to 10%. In this particular example and in every instanceusing other continuous traveling strands, the steam or treating fluidissuing from the slots followed the curvature of the larger lower lipand separation of the fluid and the strand was immediate and complete.

Pressures used within the fluid may vary over a large range as forexample between 5 and 50 lbs. gauge pressure, depending upon thematerial being treated and the substance being used as the treatingmaterial. For olyacrylonitrile yarns, steam is usually preferred in thedrawing step and pressures ranging from 30 to 45 lbs. gauge arepreferred. The fiow of the fluid depends also on the difference betweenthe pressure within the vessel and that without. This difference neednot be great but should be about 5 The various values for the ratio r/Rand for the distance T are not limited to those shown but may be variedconsiderably depending upon the size and shape of the material beingtreated and to some extent upon the treating material being used. Bothlips need not be curved. The upper lip may be at a sharp angle and r maybe zero. With the upper lip at a sharp angle, very effective control ofthe steam flow was obtained. The use of sharp edges, however, leads tomore mechanical wear on the articles and. for that reason, rounded edgesare preferred. Such an upper lip, as shown in Figure 6 in which 1' is 4inch, has the advantages of a rounded lip and a sharp angle. The radiusof the upper lip may also be equal to that of the lower lip in whichevent the steam is deflected either up or down but not outwards. Forconvenience it is preferred to have the fluid deflected downwards andfor control 1' should be slightly less than R and preferably should beno greater than 095R. R may be very large, as, for example, infinity orthe radius of a flat plate extendin beyond the upper lip. The ratio r/Rmay then vary from 0 to about 0.95. Upper lips inch in diameter andlower lips inch in diameter are generally satisfactory. For mostpurposes, the distance T should be no more than 0.05 inch. The apparatusmay be modified so that either or both of the rounded edges are moveableto provide for adjusting the distance T. Such adjustment is an advantagein that fluid loss may be reduced during operation and yet provisionsmay be made for large openings to facilitate string-up or the cleaningout of fluff, dirt or plugs. Simultaneously such rolls or cylinders asshown in Figure 3 may be positively driven in the direction of the flowto enhance the separation of the fluid, such as a liquid, from the yarn.

The apparatus of this invention may be applied to the treatment oftraveling strands as for example continuous filaments for fabrics,yarns, wires, rods, tubing and in general of any continuous filamentarystructure whether natural or synthetic in nature. When films are beingprocessed it is preferred to draw them up around the upper lip formingor approaching a radius 1. Similarly, in practice with yarn, the yarn isusually drawn upwards at an an le of about 5 to above the horizontal.

The simplicity and economy of construction and operation of apparatus inthis invention constitutes a decided advantage. The traveling strandbeing treated passes freely through the chanber and receives uniformtreatment. The treating fluid being employed is readily and completelyseparated from the traveling strand as the traveling strand enters andleaves the chamber. The escaping fluid is easily conducted away andrecycled, with the prevention of undesirable atmospheric contaminationand with the elimination of safety hazards and without the use of bulkyequipment such as hoods and ducts.

Any departure from the procedure described herein which conforms to theprinciples of the invention is intended to be included within the scopeof the claims below.

I claim:

1. Apparatus for the treatment of a traveling strand with a fluid whichcomprises a substantially closed chamber having an inlet for the saidfluid and an inlet orifice and outlet orifice for the traveling strand,these said orifices being also outlets for the said fluid and beingformed .by two rounded edges extending outwardly from said chamber, saidedges being situated one above the other, the lower rounded edgeextending beyond the upper rounded edge.

2. Apparatus for the treatment of a traveling strand with a fluid whichcomprises a substantially closed chamber having an inlet for the saidfluid and an inlet orifice and outlet orifice for the said travelingstrand, these said orifices being also outlets for the said fluid andbeing formed by two rounded edges of different radii located close toeach other and extending outwardly from said chamber, said edges beingone above the other, the lower rounded edge extending beyond the upperrounded edge.

3. Apparatus in accordance with claim 2 in which the distance of onerounded edge to the other roundedv edge is no more then 0.05 inch.

4. Apparatus in accordance with claim 2 in which the ratio of thesmaller radius to the larger radius varies from 0 to about 0.95.

5. Apparatus for the treatment of a traveling strand with a fluid whichcomprises a substantially closed chamber having an inlet for the saidfluid and an inlet orifice and an outlet orifice for the said travelingstrand, these orifices being also outlets for the said fluid and beingformed by an upper, rounded edge and a lower, rounded edge located closeto the said upper, rounded edge, the radius of the lower, rounded edgebeing larger than that of the upper, rounded edge and the lower roundededge extending beyond the upper rounded edge, both of said edgesextending outwardly from said chamber.

6. Apparatus in accordance with claim 5 in which the radius of the saidupper edge is no more than 0.95 of that of said lower edge.

7. Apparatus in accordance with claim 5 in which the distance betweensaid upper and said lower edges is no more than 0.05 inch.

8. Apparatus in accordance with claim 5 in which the said upper edgecontains grooves.

9. Apparatus in accordance with claim 5 in which the said upper edge isrounded on a circle having a diameter of 1% of an inch and the saidlower edge is rounded on a circle having a diameter of /8 of an inch.

10. Apparatus in accordance with claim 5 in which the said lower edgecontains an escape slot and a lateral passage for removal of escapingfluid.

WILLIAM THOMAS REED KINRAIDE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 879,867 Gray Feb. 25, 19081,170,228 Elliott Feb. 1, 1916 1,633,5a8 Jones June 21, 1927 2,119,261Andrews May 31, 1938 2,144,919 Gautreau Jan. 24, 1939 2,376,839 WanskerMay '22, 1945

